1. Technical Field
This invention relates generally to methods and apparatus for forming a surgical opening and providing guidance for an instrument while inside a body cavity with an external guidance apparatus, and more particularly to methods and apparatus for performing a transurethral (inside-out) suprapubic cystostomy, associated urological procedures and other surgical procedures.
2. Related Art
It is well known in the medical profession that many people experience bladder emptying problems (either urinary retention, or urinary incontinence). When severe, both conditions require drainage with a catheter. There are various factors that contribute to bladder outlet obstruction/urinary retention (BOO), such as, complications resulting from surgery, diseases, injuries, and aging. Some conditions require only a temporary solution, while others may require a more permanent solution. In addition to the open surgery method of placing a catheter, there are three known methods currently used to resolve urinary retention problems. The first method is known as clean intermittent self-catheterization (CISC). As the name suggests, this method is performed by the patient, using a clean but typically non-sterile technique 3 to 4 times daily. The patient inserts a catheter into their bladder through the urethra at regular intervals over the course of the day. Although this is presently believed to be the preferred method, it can be painful, awkward, depending on available privacy, and otherwise difficult, particularly for modest, elderly and/or incapacitated persons. In addition, complications such as urethral perforation, bladder perforation or stricture formation can occur, particularly in men, and urinary tract infections (UTI) often result from performing the procedure as the procedure is generally “clean” but not sterile.
The second method, and believed to be the most commonly used, is known as a urethral Foley catheterization (UFC). In this process, a physician or nurse inserts a Foley catheter into the bladder through the urethra. The Foley catheter has an internal balloon near its tip that is inflated to maintain the catheter within the bladder. Although this method is the most commonly used, it has many potential problems. With this method, urinary tract infections occur generally at a rate of 3-10 percent per day with an indwelling catheter maintained within the bladder, with about 5 percent of the patients developing bacterial blood infections (bacteremia).
The third method is known as a suprapubic cystostomy (SPC), and it includes two different types of procedures that are performed by a urologist usually employing intravenous (IV) sedation or local anesthesia while usually under hospital care. These procedures can be performed as a standalone procedure or in conjunction with another in unrelated surgical procedures. The first procedure is commonly referred to as a percutaneous or “outside-in” trocar punch procedure, and the second procedure is conversely referred to as a transurethral (“inside-out”) or endocystostomy procedure. The SPC methods are predominantly used in the U.S. when long-term drainage is desired, and it is used internationally for both short and long-term drainage. The percutaneous punch “outside-in” procedure is by far the more commonly used method of the two, and it entails inserting a large bore hollow needle through the abdomen and then into the bladder. This procedure requires the bladder to be inflated or distended with water to create a firm abdomen to push against while inserting the hollow bore needle due to tissue resistance. The percutaneous punch method whereby a hollow needle is pushed through the abdomen into the bladder is a blind procedure and relies on physical feel and skill and experience of the physician to safely puncture the bladder. Thereafter, a smaller catheter is inserted through the hollow needle into the bladder. Drawbacks to this method include unreliable drainage due to a high rate of clogging and kinking of the catheter drainage tube. The percutaneous punch method has increased safety issues with high morbidity and mortality rate near 2%, usually from unrecognized puncturing of bowel. These two procedures cannot be safely performed on the morbidly obese patient, a patient population that is increasing, currently estimated to be more than 12 percent of this targeted patient population.
The current transurethral (“inside-out”) procedure is performed by inserting a hollow instrument with a blunt tip, commonly referred to as a sound, through the urethra into the bladder. The Sound has a tip that is typically advanced to penetrate through the bladder and abdominal wall and extend outside the abdomen. The surgeon is usually required to make an incision in the abdomen and facia, down to the tip of the sound to allow the blunt tip of the sound to advance through the abdomen exiting the skin. In the cases where the sound tip cannot reach outside the abdomen, the surgeon must make a larger incision in the abdomen with a scalpel to allow for attachment of the catheter while the sound tip resides inside the abdomen. With the sound finally exposed outside the abdomen, a catheter is attached to the end of the sound and drawn back into the bladder and out of the patient through the urethra along with the withdrawn sound. Upon being pulled and exiting the patient through the urethra, the catheter is then detached from the sound and pulled back into the bladder, whereupon a balloon on the catheter is inflated in an effort to maintain the catheter in a desired position within the bladder. Some of the drawbacks to this method include, a relatively high cost of the reusable surgical instruments, requiring sterilization between procedures, the catheter can be difficult to attach to the sound and once attached can disconnect during the procedure requiring the procedure to be repeated, the location of the deflated catheter balloon within the bladder can be difficult to ascertain prior to inflating the catheter balloon, and additionally, it can often not be effectively used to safely perform the procedure on obese and morbidly obese patients.